Calculate Maximum Momentum of Pelle Cycling up a Hill

  • Thread starter Izekid
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It's about the torque Pelle can generate by pushing on the pedals of his bike. The torque is given by the length of the lever arm (radius of the pedals) multiplied by the force applied (Pelle's weight). In summary, Pelle can generate a maximum torque of 120Nm by standing up and pushing all his weight on the pedals of his bike, which have a radius of 18cm.
  • #1
Izekid
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Pelle who weights 68 kilos, cycles up a steep hill. He stands up and pushes all his weight on the pedals. Pedals moves in a circle with the radie 18cm. Which is the biggest momentum he can affect the pedals with

Well my answer is wrong but this is how I did
Because I don't know the answer I take

m2= 9,82*(0,18)^2 = 0,318168/6,67*10^-11 = 4770134933
Which is the second mass

M1 = His weight 68kg

Then I take 68*4770134933 =3,24691754^10*-11 * 6,67*10^11 = 21,635424
and then I finely dived it which is 21,635424/0,18^2 = 667,76 N

I get but it's not right answer should be 120Nm please help me !
 
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  • #2
The unit of moment of a force (often called torque) is Nm, and the equation:
[tex]\mathbf{M} = \mathbf{r} \times \mathbf{F}[/tex]

This problem has little to do with gravitation.
 
  • #3


Hello! It seems like you have attempted to use the formula for calculating momentum, which is correct. However, there seems to be some confusion with the units and values used in the calculation. Here is how you can correctly calculate the maximum momentum of Pelle cycling up a hill:

First, let's determine the force that Pelle is applying on the pedals. We know that Pelle's weight is 68kg and he is pushing all his weight onto the pedals. This means that the force he is applying on the pedals is equal to his weight, which is 68kg x 9.82m/s^2 (acceleration due to gravity) = 667.76 N.

Next, we need to determine the radius of the pedals in meters. We are given the radius in centimeters, so we need to convert it to meters by dividing it by 100. This gives us a radius of 0.18m.

Now, we can use the formula for calculating momentum, which is p = mv, where p is momentum, m is mass, and v is velocity. In this case, the mass is the force applied (667.76 N) and the velocity is the distance traveled per unit time, which is the circumference of the circle that the pedals are moving in. The circumference can be calculated as 2πr, where r is the radius (0.18m). This gives us a velocity of 2π x 0.18 = 1.13 m/s.

Plugging these values into the formula, we get p = 667.76 N x 1.13 m/s = 755.33 Nm. This is the maximum momentum that Pelle can affect the pedals with while cycling up the hill.

I hope this helps clarify the calculation for you. Just remember to pay attention to the units and use the correct values in the formula. Keep up the good work as a scientist!
 

1. How is maximum momentum calculated?

The maximum momentum of an object can be calculated by multiplying its mass by its velocity. In the case of Pelle cycling up a hill, it would be calculated by multiplying Pelle's mass by his velocity as he cycles up the hill.

2. What is the unit of measurement for maximum momentum?

The unit of measurement for maximum momentum is kilogram-meters per second (kg*m/s). This unit is derived from the units of mass (kilograms) and velocity (meters per second) used in the calculation.

3. How does the incline of the hill affect Pelle's maximum momentum?

The incline of the hill can affect Pelle's maximum momentum in two ways. First, it can increase the force needed to overcome gravity and maintain a constant velocity. Second, it can decrease the efficiency of Pelle's pedaling, resulting in a lower velocity and therefore a lower maximum momentum.

4. Is maximum momentum the same as kinetic energy?

No, maximum momentum and kinetic energy are two different concepts. Maximum momentum is a measure of an object's motion at a specific moment, while kinetic energy is a measure of an object's energy due to its motion. However, they are related since an object's kinetic energy is equal to half of its mass multiplied by the square of its velocity, which is also the equation for maximum momentum.

5. Can the maximum momentum of Pelle cycling up a hill be increased?

Yes, the maximum momentum of Pelle cycling up a hill can be increased by either increasing his mass or increasing his velocity. However, there are limits to both of these factors, as a heavier Pelle would require more force to pedal and a faster Pelle may not be able to maintain his speed on the incline of the hill. Additionally, factors such as the bike's gear ratio and Pelle's pedaling technique can also affect his maximum momentum.

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